Apparatus having separatable and assemblable portions and control means therefor



June 6, 1950 s. A. HUFFMAN APPARATUS HAVING SEPARATABLE AND ASSEMBLABLE PORTIONS AND CONTROL MEANS THEREF'OR origina Filed Aug. 14, 1941 Nmflnm 11m. 1 l l I I l l I l I I I l I I I I I@ NVENTOR Jamas/Huffman June 6, 1950 1s. A. HUFFMAN 2,510,890

APPARATUS HAVING SEPARATABLEAND AssEMBLABLE PoRToNs AND CONTROL MEANS THEREFOR Original Filed Aug. 14, 1941 5 Sheets-Sheet 2 INVENTOR Samuel/l. Huffman June 6, 1950 s. A. HUFFMAN APPARATUS HAVING SEPARATABLE AND ASSEMBLABLE PORTIONS AND CONTROL MEANS THEREFOR Original Filed Aug. 14, 1941 3 Sheets-Shes?l 3 mv w wm mag? NN. 9v L@ wm.. n E.;

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INVENTOR Y Sue/ A Huffman .w .SPN

Patented June 6, 1950 APPARATUS HAVING SEPARATABLE AND ASSEMBLABLE PORTIONS AND CONTROL MEANS THEREFOR Samuel A. Huffman, Pasadena, Calif., assignor to Miller Printing Machine Co., Pittsburgh, Pa., a corporation of Pennsylvania Continuation of application Serial No. 406,800, August 14, 1941. This application July 11, 1945,

Serial No. 604,448

This invention relates to apparatus having separatable and assemblable portions and control means therefor. It relates particularly to apparatus comprising portions relatively movable toward and from cooperative relation in which they are adjacently positioned. The invention has to do primarily with means for effecting and stopping relative movement between such portions and connections facilitating such relative movement, relieving the parts of strain and providing for the safety of workmen. This application is a continuation of my copending application Serial No. 406,800 now abandoned.

The invention is of wide application to apparatus having separatable and assemblable portions. I have adapted it particularly to printing apparatus wherein it has important advantages. However, I regard the invention as having particular advantages when applied to material handling apparatus of various kinds, including, of course, sheet handling apparatus. The term material handling apparatus is used herein as a term of broad definition and not of limitation and comprehends any apparatus in which material of any character is handled or treated. Purely for purposes of explanation and illustration the invention Will be described as embodied in printing apparatus. The word printing as used herein comprehends not only the application of ink to sheets but also analogous treatment thereof customarily performed in similar apparatus as, for example, cutting and creasmg.

I have found that the invention is ideally suited for, and produces important new and useful results when embodied in, relatively heavy or ponderous printing apparatus. The apparatus selected for illustration of the invention consists of a printing press comprising a printing couple and a feeder therefor. The press may be of any type but is shown as of the at bed and cylinder type. The feeder likewise may be of any type but is shown as one which automatically lifts a pile of sheets during operation of the press and feeds the sheets singly from the top of the pile to the press. The press and feeder are made separable so that when printing is not being done and it is desired to work on the form or other parts of the press the feeder may be retracted away from the press to an out of the way inoperative position. To this end I preferably provide for relative rectilinear movement between the press and feeder. tionary or both may be movable relatively to the floor I prefer to mount the pressfstationarily and While either may be sta- Claims. (Cl. 271-8) to move the feeder toward and from the press. Thus when the feeder is moved out to inoperative position away from the press there is room for workmen to stand between the press and the feeder to work on the press or, if desired, on the feeder.

In the illustrated embodiment of the invention the press and feeder may be considered as relatively heavy or ponderous. Considerable force is required to move the feeder toward and from the press. It may, for example, carry a stack of sheets weighing thousands of pounds in addition to its own substantial weight. I preferably employ screw means for moving the feeder toward and from the press. I provide a screw connected with the feeder and a nut connected with the press and threadedly receiving the screw and means relatively turning the screw and nut. I have found that when moving means of this character is employed there is danger of locking of the screw means if the feeder is driven thereby up against and in contact wth the press. Even though a powerful motor may be used the screw means may thus be so tightly locked that the motor will not operate in either direction and the apparatus has to be disassembled and reassembled with the parts in operative relation. To avoid this diiculty when employing the screw drive I utilize means for stopping movement of the feeder toward the press just prior to contact between the feeder and press. Such means may conveniently comprise a limit switch breaking the motor circuit. I also preferably employ a limit switch for limiting outward movement of the feeder. The limit switch for limiting inward movement of the feeder is preferably set so that under any condition of loading the feeder will never forcibly strike the press. Not only is this disadvantageous from the standpoint of locking the moving means but it may result in damage to the press or feeder or both.

- `Since I preferably stop the movement of the feeder toward the press before it fully reaches operative position relatively to the press I preferably provide means for drawing the feeder up tightly against the press into operative position. In order that such means may operate without disconnecting the power operated moving means I preferably provide ya lost motion connection permitting drawing of the feeder up against the press without the necessity of disconnecting any part of the apparatus. Also when heavy or ponderous apparatus is employed the lload on the motor is very heavy .if it be attempted to start the motorv from rest under full load, necessitating use of a 3 motor of large size. I nd that I can use a motor of considerably smaller size and less capacity by providing for starting up the motor before movement of the feeder commences so that the motor will be up to speed when the full load is applied to it. The lost motion connection above mentioned preferably enables the motor to start before relative movement between the feeder and press commences.

that the nut may have limited movement in a direction parallel to the axis of the screw. Inthe structure shown in the drawings the screw/1S.

fastened non-rotatively to the feeder and the nut is mounted in the press. An electric motor is also mounted in the press for turningthe nut. The

nut is mounted in a collar and provision is madeV for limited lost motion of the nut in the collar in a direction parallel to the axis of the screw. As above mentioned, this enables the feeder to be drawnup tightly against the press without. disconnecting the driving'mechanism andalso enables 'the motor'to .get up to speed-before-taking the full load when the feeder istol be moved toward or away from'the press.

I preferably mount the means for relatively moving the portions of the apparatus so that the part of such means which is; connected with one of said portions is connected therewith loosely lso as to be free to -`partake of limited movement in any direction and especiallytransversely of the directionof relativemovement between-said portions. Preferably a transverselost motion connection is provided between said part andthe portion of the apparatus which carries it. In thestructureshownin the drawings the screw is carried by a bracket which is loosely mounted on'. aL portion of the feeder frame which allows the screw to shiftslightlyduring operation. Any irregularities Vin the parts, as, for example, slight bendingxof the screw, are thus compensated for. There is some relativedefiection and settling between vthe feeder and the press during kandattlle end of relative movement therebetween which tends to cause binding of the screw and nut and the looseA mounting ofv thescrew on the feeder frame obviates vsuch tendency.

I preferably employ a slippable connection, such as a friction connection, between the motor and the moving means so .that if a Workman should be in between the feeder and press when the feeder moves toward the `press and become caught therebetween the addedresistance to movement will simply result inslippage of the connection where.- by crushing of the workman4 will be avoided. This `connection is-also of advantage in case tools are left between the feeder and press which-would result in damagev if the feeder were positively moved despite the yamount of resistance interposed. Iiind it desirable to employ a friction belt drive for the feeder, although other friction or s-lippable drives may be used.

I provide apparatus comprising 'portions rela- Ativelymovable toward and from cooperative relation in which theyv are adjacently positioned, rst movingmeans for relatively moving said portions, meansoperated by at least one offsaid portions. when said portions upon relative movement toward each other reach predetermined relative positions, for rendering inoperative said rst moving means and stopping relative movement of ,said'portions while they yare stillslightly spaced aparty whereby to avoid their striking forcibly together, andsecondamoving-means operable upon said stoppingof said-relativemovement.tofurther I nd it convenient to mount? the screw and nut on the pressand feeder so.

relatively move said portions toward each other into cooperative relation. Preferably the first moving means comprises cooperating members, oneccnnected with each portion, and an operatng'member connected'fwith one of the cooperating members and operable to travel relatively to the other thereof whereby to relatively move said members and hence said portions, said operating member being movable relatively to the one of saidcooperating'members with which it is connected-upon relative movement of said portions toward-each otherA into cooperative relation by the secondmoving means.

Other details, objects and advantages of the invention will become apparent -as the following description of a present preferred embodiment thereof proceeds.

In the accompanying drawings I have shown a present preferred embodiment of the invention, in which Figure 1 is alfragmentaryside elevational view of a sheet feeder shown iii-operative relation to a .flat bed and cylinder printing press;

Figure 2 is .-a view similar to Figure 1 but showingA the feeder moved out to inoperative position relatively to the press;

Figure 3 .is a fragmentary horizontal cross-sectionalview to enlarged scale taken on the line III-III of Figure 1;

Figure fris ,a I.fragmentary vertical longitudinal cross-sectionalview taken on the line IV-IV of Figure 3;

Figure 5 is a fragmentary horizontal cross-sectional view of a portion kof the structure as shown in Figure 1;.

Figure (iis va fragmentary longitudinal crosssectional view to enlarged scale, with a portion cut away. theA screwforgmovng the feeder toward and from the press and its cooperating mechanism:

Figure 1'7-is `a vertical transverse cross-sectional view taken on the line VII- VII of Figure 6; and

Figure 8 is a vertical transverse cross-sectional view. to-enlargedscale taken on the line VIII- VIII of Figure 5.

Referring now more -particularly to the drawings, there is shown at 2 a cylinder of a printing press. The press may be considered as a press of the flat bed and cylinder typeto which sheets are fedsingly in well known manner. The cylinder 2 and the dat bed cooperating therewith constitute the printing couple. Since the-specific structure of the press or printing couple forms no part of the present invention such structure is not shown in detail.

Reference numeral 3 designates generally a feeder adapted .to cooperate with the press to feed sheets thereto. The feeder. is preferably movable between operative andinoperative positions relatively to the press upon rails 4 which extend out in a straight line from the feeder end of the press. Thus the feeder ismovable rectilinearly into and out of yoperativeposition relatively to the press. In Figure 1 the feeder is shown in operative position and-in Figure 2 it is shown moved out to inoperative position. When the feeder is inthe inoperative position vas shown in Figure 2 it provides a substantial space between the press and feeder, allowing workmen to enter and work upon the press-or feeder.

Reference numeral 5 designates a portion of theffeeder framewhich extends downwardly to a position close to the floor where it has a horizontal extension 6. Fastened to the extension 6 by screws 'l is a bracket Sfhaving a cylindrical horizontal recessffbored therein. The bracket 8 has two vertical bores 8a therethrough each of which loosely receives a sleeve 'la whose length is somewhat greater than the thickness of the bracket 8, the screws 'I extending within the respective sleeves 1a. A washer 'Ib lies between the head of each screw 1 and the top of the corresponding sleeve 'Ia and the screws are screwed down tight into the extension 6 so that the sleeves are xedly positioned relatively to such extension. By reason of the fact that the internal diameter of each bore 8a, is materially greater than the external diameter of the sleeve 'Ia therein and the fact that the length of each sleeve 1a is materially greater than the thickness of the bracket 8 such bracket, although held to the extension 6 by the screws, is free to partake of limited movement in any direction relatively to the extension. The reason for thus mounting the bracket will presently appear.

A screw I0 has integral with one end a projection I I which enters the recess 9 in the bracket 8. A set screw I4 threaded into the top of the bracket 8 and intersecting the recess 9 engages the projection I I of the screw I il to hold the screw xedly relatively to the bracket. After the screw Hl is thus held relatively to the bracket by the set screw I4 a tapered bore I3 is formed in the bracket 8 and projection II and a tapered pin I2 is driven thereinto to insure permanent proper Y relative positioning of the screw and bracket. After insertion of the pin I2 the set screw HI may be removed if desired.

A portion of the press frame is shown at I5. Bolted to the press frame by bolts IS is a collar Il which at all times is iixedly positioned relatively to the press frame. Provision is made for adjusting the position of the collar Il relatively to the press frame, but the collar in any adjusted position is immovably xed to the press frame. A nut Ill is in threaded engagement with the screw Ill and has an elongated cylindrical outer surface I9 whose diameter is slightly smaller than the internal diameter of the collar I'l so that the nut may slide within the collar in the axial direction. The nut has an integral flange at one end and at the other end has connected therewith by screws 2l a pulley or sheave 22. Thus Athe nut I8 is in effect flanged at both ends but.

VI'l in the axial direction so that the collar allows limited axial movement of the nut relatively thereto, such axial movement being limited in one 'direction by engagement of the flange 28 with the collar and in the other direction by engagement of the sheave 22 with the collar.

Mounted on the press frame is an electric motor 23 having a shaft 24 carrying a pulley 25. A friction belt 25 shown as being in the form of a V-shaped flexible composition belt extends about the pulleys 22 and 25 as clearly shown in Figure 5. The motor 23 is a reversible motor so that through the belt 26 it can turn the nut I8 in either direction. When the motor is operated to turn the nut in one direction after having last previously turned it in the opposite direction the nut will travel upon the screw Ill until either the flange 20 or the sheave 22, depending upon the direction of travel, engages the collar il. During this travel of the nut the press and feeder will both remain stationary. Also during such travel of the nut the motor 23 will have time to get up to operating speed. As soon as the trailing flange of the nut (either the flange 28 or the sheave 22) engages the collar I1 further travel of the nut along the screw l0 is positively prevented. Continued operation of the motor and turning of the nut then causes the screw I0 to travel axially since the screw is held against rotation in the feeder frame. Also since the screw is fixed to the feeder axial travel of the screw causes similar axial travel of the feeder upon the rails 4. The direction of travel of the feeder relatively to the press depends upon the direction of operation of the motor 23 and the direction of turning by motor of the nut I8.

The loose or floating mounting of the bracket 8 on the feeder frame extension E allows for limited relative movement between the bracket and the feeder frame whichv in turn allows the screw I0 to shift slightly during operation due t0 any slight irregularities of the parts or, for example, in the event that the screw I8 should become slightly bent. Also there is some relative deflection and settling between the feeder and the press during and at the end of relative movement therebetween which, if the bracket 8 were rigidly attached to the feeder frame extension 6, would result in a tendency of the screw I0 to bind with the nut I8. Any such tendency to bind is obviated and any slight irregularity of the parts is compensated for by the loose or floating mounting of the bracket 8 upon the feeder frame extension 6.

Connected to the outer end of the screw IIJ is a bracket 2l carrying a limit switch operating cam 28. The cam 28 is connected with the bracket by bolts 29 which pass through an elongated slot 30 in the cam whereby the cam may be adjusted along the bracket axially of the screw. Carried by the press frame are two limit switches 3l and 32. The limit switch 3| has an operating arm 33 and the limit switch 32 has an operating arm 3A. The operating arms of the limit switches are in longitudinal alignment and in the path of movement of the cam 28 as the feeder moves along the rails 4. The limit switches 3| and 32 are connected into the circuit for operating the electric motor 23 in such manner that when the motor is turning in the direction to move the feeder toward the press (toward the left viewing Figure 5) the cam 28 will operate the limit switch 3l to open the motor circuit just as the feeder is reaching the position in which it is to be stopped, and when the motor is turned in the direction t0 move the feeder away from the press (toward the right viewing Figure 5) the cam 28 will operate the limit switch 32 to open the motor circuit just as the feeder is reaching the position in which it is to be stopped.

The parts are so related that when the feeder is moving toward the press the limit switch 3l operates to open the motor circuit in time so that the feeder under any condition of loading will always stop before forcibly striking the press. The feeder may gently touch the press, but as a rule the limit switch will operate soon enough so that when the feeder stops it will be spaced from the press a fraction of an inch. Thus binding of the screw and nut is prevented. Also, when the feeder is moving away from the press the limit switch 32 will prevent overtravel of the feeder and insure its always stopping in approximately the same position when moved to inoperative position.

A portion of the feeder frame is shown at 35 (see Figure 3). A shaft 3E is mounted fOr rotation in the feeder frame, passing through the portion 35 and extending transversely of the feeder and also being journaled in the opposite frame portion. Keyed to the shaft 36 adjacent each side of the feeder is an eccentric 3l. A latch 3S having a hook end 39 is mounted about each of the eccentrics 31, each of such latches having a hub portion 4l] receiving the eccentric. Each of the feeder side frames carries a pin 4I which prevents the latch adjacent that side of the feeder from falling' down. Each latch hub 5S carries a pin i2 extending parallel to the shaft SB. integral with each of the eccentrics 31 is a collar 43 carrying a radial pin 44. At each side of the press frame is a projection 45 receiving a screw 46. Each of the screws 4S lies horizontally with its head away from the feeder. Keyed to the shaft 36 outside one of the side frames is an operating handle 4'! for turning the shaft 3'6. The handle 4l has a hub 48 having two opposed shoulders 49 andV 50. A pin 5l is connected with the side frame and projects outwardly therefrom in the path of the shoulders 49 and 50 when the handle 41 is moved about the axis of the shaft 3S.

As explained above, when the feeder has been in its outward or inoperative position and is to be moved to operative position relatively to the press the motor 23 is operated to turn the nut I3 in such direction as to move the feeder toward the press. Such movement is terminated by opening of the limit switch 3l by the cam 28. This is done at such time, as above explained, that the feeder comes to rest a short distance away from the press.

Preferably when the feeder is moved up to its position spaced slightly from the press as thus described the handle 4l and latches 38 are in the position shown in Figure l but with the latches in a slightly lower angular position resting upon the respective pins 4i. The function of these pins, as above explained, is simply to keep the latches 3S from falling down so low that they will not properly enter into engagement with the projections 45 of the press. As the feeder approaches the press the inclined nose surfaces 52 of the latches 38 ride up on the respective projections 45 but the hooks 39 do not quite reach the position shown in Figure 1 since the feeder is somewhat spaced from the press.

With the parts positioned as just explained the presslnan moves the handle 4l' in the clockwise direction. viewing Figure 1, through a small angle. As the parts are shown in Figure 1 the eccentrics Fi? are approximately on dead center away from the projections 45 of the press. Consequently turning of the handle il in the clockwise direction tends to swing the eccentrics downwardly and toward the press, thus pushing the latches @Si toward the left viewing Figure 1. The latches will drop into position with their hooks against the heads of the screws 4S, whereafter rthe handle 4l is returned to the position of Figure 1 by moving it in the counter-clockwise direction about the axis of the shaft 3S. This reinirns the eccentrics 31 to their dead center positions and draws the feeder tightly up against the press. The screws 46 may be adjusted as desired to insure proper drawing up of the feeder against the press.

When the feeder is to be moved away from the press the handle 4l is turned in the clockwise direction viewing Figure 1 until the shoulder 49 engages the pin 5i, as shown in Figure 2. The rst part of the turning movement of the handle 47 swings the eccentrics 3l downwardly and toward the left as above explained, thus loosening the latches 38, and when the pins 44 engage the .respective pins 42 the latches are lifted-to the position shown in Figure 2. The pins 44 engage the pins 42 shortly before the shoulder 4! engages the pin 5i and not until after the eccentrics have been turned far enough to loosen the latches. The feeder is then free to be moved away from the press, which, as above explained, is accomplished by operating the motor 23 in the direction to turn the screw I0 to move the feeder toward the right viewing Figure 1.

When the handle 4l is operated as above explained to draw the feeder up tightly against the presssuch relative movement between the feeder and the press is accompanied by movement of the screw I0 and nut I8 relatively to the collar I1, the lost motion between the collar and the nut being sufficient to allow of tightening up of the feeder to the press as explained. When the motor 23 is stopped after moving the feeder toward the press the ange 20 will be in engagement with the collar l1 and the sheave 22 will be spaced from the collar l'. Consequently drawing up of the feeder toward the press allows the nut I8 to slide toward the left viewing Figure 6 within the collar l1. Preferably the sliding of the nut within the collar is through a distance substantially less than the clearance provided between the nut and the collar so that when the feeder is positioned tightly against the press there is substantial clearance between the sheave 22 and the collar Il. This clearance is desirable so that when the motor is subsequently operated to move the feeder away from the press the motor will have time to get up to speed before the sheave 22 engages the face of the collar Il. As the parts are shown in Figure 6 the sheave 22 is flush against the collar I1, this being the position of the parts when the feeder is being moved out away from the press. The force moving the feeder away from the press is exerted between the right-hand face of the collar Il and the left-hand face of the sheave 22 viewing Figure 6.

Due to the freedom of movement of the nut I8 within the collar l] the belt 26 partakes of slight angular displacement between its position when the feeder is moving in and its position when the feeder is moving out. However, the length of the belt and its flexibility are such as to allow for this angular displacement. The belt may slip upon the pulley 22 when any obstruction is offered to movement of the feeder. rEhus if a workman is in between the press and the feeder when the feeder is moved toward the press the resistance imposed by the workmans body will result in slippage cf the belt 26 and avoid serious injury to the man. Similarly, injury to the apparatus due to leaving tools or other obstructions between the press and the feeder is avoided by reason of the provision of the belt 2t.

The drawings show, in some cases more or less vdiagrammatically or fragmentarily, other elements of the apparatus, but since such other elements may be conventional and do not form part of the vpresent invention they will not be described in detail. It is of course to be understood that means are provided in the feeder for taking sheets "from the top of the pile in the feeder and feeding them one by one to the press, after which they pass to a suitable delivery and are piled up.

The pile support in the feeder is shown at 53, the

pile of sheets being omitted for the sake of clarity. Means are provided for raising the pile support, such means preferably being of the type described and claimed in Patent No. 2,334,223.

The sheets are moved downthe feed board shown 'at 54 and registered to the press in a manner known in the art.

While I have shown and described a present .preferred embodiment of the invention it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied within the scope of the following claims.

I claim:

1. Apparatm comprising portions relatively movable toward and from cooperative relation in which they are adjacently positioned, first moving means for relatively moving said portions, means operated by at least one of said portions, when said portions upon relative movement toward each other reach predetermined relative position, for rendering inoperative said first moving means and stopping relative movement of said portions while they are still slightly spaced apart, whereby to avoid their striking forcibly together, and in such relative positions that the second moving means hereafter mentioned may become operative and second moving means to further relatively move said portions toward each other into cooperative relation, said rst moving means comprising a screw connected with one of said portions, a collar connected with the other of said portions and through which the screw passes, a nut in threaded engagement with the screw and positioned within the collar, means for limiting relative movement between the nut and the collar axially of the screw and means for rotating the nut to cause relative travel between the nut and the screw axially of the screw whereby to relatively move said members and hence said portions, the nut being movable relatively to the collar axially of the screw upon relative movement of said portions toward each other into cooperative relation by said second moving means.

2. Apparatus comprising portions relatively movable toward and from cooperative relation in which they are adjacently positioned, iirst moving means for relatively moving said portions, means operated by at least one of said portions, when said portions upon relative movement toward each other reach predetermined relative position, for rendering inoperative said rst moving means and stopping relative movement of said portions while they are still slightly spaced apart, whereby to avoid their striking forcibly together, and in such relative positions that the second moving means hereafter mentioned may become operative and second moving means to further relatively move said portions toward each other into cooperative relation, said first moving means comprising a screw connected with one of said portions, a collar connected with the other of said portions and through which the screw passes, a, nut in threaded engagement with the screw and positioned within the collar, the nut having ange means adapted to engage the collar upon relative movement between the nut and the collar axially of the screw whereby to limit such relative movement, and means for rotating the nut to cause relative travel between the nut and the screw axially of the screw whereby to relatively move said members and hence said portions, the nut being movable relatively to the collar axially of the screw upon relative movement of said portions toward each other into cooperative relation by said second moving means.

3. Apparatus comprising portions relatively movable toward and from cooperative relation in which they are adiacently positioned, rst moving means for relatively moving said portions, said first moving means comprising a screw connected with one of said portions, a collar connected with the other of said portions and through which the screw passes, a nut in threaded engagement with the screw and positioned within the collar, means for limiting relative movement bet-Ween the nut and the collar axially of the screw and means for rotating the nut to cause relative travel between the nut and the screw axially of the screw whereby to relatively move said members and hence said portions, means operated by at least one of said portions, when said portions upon relative movement toward each other reach predetermined relative position, for rendering inoperative said nut rotating means and stopping relative movement of said portions while they are still slightly spaced apart, whereby to avoid their striking forcibly together, and in such relative positions that the second moving means hereafter mentioned may become 0perative and second moving means to further relatively move said portions toward each other into cooperative relation, the nut being movable relatively to the collar axially of the screw upon relative movement of said portions toward each other into cooperative relation by said second moving means.

4. Apparatus comprising portions relatively movable toward and from cooperative relation in which they are adjacently positioned, rst moving means for relatively moving said portions, said first moving means comprising a screw connected with one of said portions, a collar connected with the other of said portions and through which the screw passes, a nut in threaded engagement with the screw and positioned within the collar, the axial dimension of the nut being greater than the axial dimension of the collar, the nut having flanges extending transversely of its axis the inner faces of which are spaced apart a distance greater than the axial dimension of the collar, and means for rotating the nut to cause relative travel between the nut and the screw axially of the screw whereby to relatively move said members and hence said portions, means operated by at least one of said portions, when said portions upon relative movement toward each other reach predetermined relative position, for rendering inoperative said nut rotating means and stopping relative movement of said portions while they are still slightly spaced apart. whereby to avoid their striking forcibly together, and in such relative positions that the second moving means hereafter mentioned may become operative and second moving means to further relativeli7 move said portions toward each other into cooperative relation, the nut being movable relatively to the collar axially of the screw upon relative movement of said portions toward each other into cooperative relation by said second moving means.

5. Apparatus comprising portions relatively movable toward and from cooperative relation in which they are adjacently positioned, first moving means for relatively moving said portions, said ilrst moving means comprising a screw connected with one of said portions, a collar connected with the other of said portions and through which the screw passes, a nut in threaded engagement 'with the screw and positioned within the collar, means for limiting relative movement between the nut and the collar axially of the screw and means for rotating the nut to cause relative travel between the nut and the screw axially of the screw'whereby to relatively move said members and Shence said portions, means operated by at least oneof said portions, whensaid .portions upon Arelative movement toward eachother-reach predetermined relative 4position, for rendering inoperative said nut rotating means and stopping relative movement of lsaid vportions lWhile they'are still slightly spaced apart,

whereby-.to avoid their striking -foroibly together, and in -such -relative positions lthat the second moving means hereafter v`mentioned may become operative 4and second moving means operable whensaidportions have been brought into-slightly spaced apart relation -as 'aforesaid to further relatively move said portions toward eachother into lcoopera-tive relation, the nut being movable relatively to the collar axially ofthe screw upon relative movementof said portions toward each other into cooperative relation by said second moving means, said secondl moving means comprising-means -eonnectedwithoneof said portions 12 for engaging `theotlier portion, :eccentric mearu for moving said last mentioned ,means :generally in the direction of relative movement A.between said portions and .manuallyoperable means :for turning said eccentric means.

SAMUEL AA.

REFERENCES CITED The following references are of record Vin the le of this patent:

UNITED STATES PATENTS Number Name Date 1,036,190 Chard Aug. 20. 1912 1,340,811 Ballman May 18, 1920 1,490,934 Petersen Jan. 2, 1923 1,670,569 Claybourn May 22, 1928 1,952,028 Hehle et al. Mar. 20, 1934 2,170,025 J ordhoy Aug. 22, 1939 2,184,296 Goebel et al Dec. 26, 1939 2,188,148 Harless Jan. 23. 1940 

